DaVinci Resolve Deliver - Using our 5120x2160 RED sample clip, we transcoded it to ProRes 4444XQ at 3840x2160.(LOWER time in seconds = FASTER)

Final Cut Pro X Render- As a test that stresses both CPU and GPU, we applied a Gaussian Blur to our 1080p sample and clicked Render.(LOWER time in seconds = FASTER)

Final Cut Pro X Export - We 'shared' the BruceX 5K project as a ProRes 4444XQ Master File(LOWER time in seconds = FASTER)

Premiere Pro Render - We selected all assets in the PPBM6 sample project and clicked Render.(LOWER time in seconds = FASTER)

Premiere Pro Export - We exported the PPBM6 project to H.264 Blu-ray 1080p format using Maximum Render Quality but not using Adobe Media Encoder.(LOWER time in seconds = FASTER)

After EffectsRender using Software - We rendered the TESTCOMP benchmark project using Software Project Setting for Video Rendering And Effects.(LOWER time in seconds = FASTER)

After EffectsRender using OpenCL and Metal - At the suggestion of a reader, we re-rendered the TESTCOMP benchmark project using OpenCL and Metal Project Settings for Video Rendering And Effects. (The Mac Pro 2010 in the graph below is for the the dual AMD 7950s. The GeForce GTX 1080 Ti was unsupported so it would only do Software rendering.)

MotionRAM Preview- Using the Atmospheric - OPEN template, we selected RAM Preview > Play Range (to render the preview in RAM). We calculated FPS by dividing elapsed time by number of frames (600).(HIGHER frames per second = FASTER)

PhotoshopFilter- We rendered the Iris Blur filter using our test image. It is one of the filters that makes use of a GPU that supports OpenCL.(LOWER time in seconds = FASTER)

LightroomExport- We exported 50 RAW images as full sized JPEG.(LOWER time in seconds = FASTER)

WHAT DID WE LEARN?
Analyzing your pro application's performance can be frustrating. Some functions are CPU intensive. Some are GPU intensive. Some are a mixture of both. In some cases the 2017 iMac 5K 4-core acquitted itself very well compared to the 12-core Mac Pro tower and 8-core Mac Pro cylinder. At other times, it was left in the dust.

We featured the 2010 Mac Pro tower with two different GPU setups. The dual Radeon HD 7950 'Mac Editions' are the last AMD GPUs that Apple blessed for the Mac Pro tower. Since the NVIDIA Pascal GPUs are the new, hot 'mad GPU science,' I included results for the GeForce GTX 1080 Ti. The AMD GPUs do best with Apple pro apps (FCPX, Motion). The NVIDIA GPUs do best with DaVinci Resolve NR playback and CUDA capable functions in Adobe apps.

In an upcoming article, we will report on the whether combining a high-end Pascal NVIDIA GPU (in an eGPU box) with the built-in AMD Radeon Pro 580 of the iMac 5K will produce the best of both worlds.

Choosing a Mac that can best handle your projects depends on what pro apps you use most and what functions within those apps that are critical to your workflow.

ADDENDUM ON JULY 13TH
The validity of our original test of the 2017 iMac 5K with 16GB of RAM was questioned by readers who noticed the competing Macs had much more RAM. Though Activity Monitor reported real memory use of under 16G on all tests, once we received a 64GB RAM upgrade kit, we retested the 2017 iMac 5K and added those results to the graphs.